39 I fear, I say, greatly for you, lest, when you boast that you will follow the Lamb wheresoever He shall have gone, you be unable by reason of swelling pride to follow Him through strait ways. It is good for you, O virgin soul, that thus, as you are a virgin, thus altogether keeping in your heart that you have been born again, keeping in your flesh that you have been born, you yet conceive of the fear of the Lord, and give birth to the spirit of salvation. “Fear,” indeed, “there is not in charity, but perfect charity,” as it is written, “casts out fear:” but fear of men, not of God: fear of temporal evils, not of the Divine Judgment at the last.
“Be not high-minded, but fear.” Love the goodness of God; fear His severity: neither suffers you to be proud. For by loving you fear, lest you grievously offend One Who is loved and loves. For what more grievous offense, than that by pride you displease Him, Who for your sake has been displeasing to the proud? And where ought there to be more that “chaste fear abiding for ever and ever,” than in you, who hast no thought of the things of this world, how to please a wedded partner; but of the things of the Lord, how to please the Lord? That other fear is not in charity, but this chaste fear quits not charity.
If you love not, fear lest you perish; if you love, fear lest you displease. That fear charity casts out, with this it runs within. The Apostle Paul also says, “For we have not received the spirit of bondage again to fear; but we have received the spirit of adoption of sons, wherein we cry, Abba, Father.” I believe that he speaks of that fear, which had been given in the Old Testament, lest the temporal goods should be lost, which God had promised unto those not yet sons under grace, but as yet slaves under the law.
There is also the fear of eternal fire, to serve God in order to avoid which is assuredly not yet of perfect charity. For the desire of the reward is one thing, the fear of punishment another. They are different sayings, “Whither shall I go away from Your Spirit, and from Your face whither shall I flee?” and, “One thing I have sought of the Lord, this I will seek after; that I may dwell in the house of the Lord through all the days of my life, that I may consider the delight of the Lord, that I be protected in His temple:” and, “Turn not away Your face from me:” and, “My soul longs and faints unto the courts of the Lord.” Those sayings let him have had, who dared not to lift up his eyes to heaven; and she who was watering with tears His feet, in order to obtain pardon for her grievous sins; but these do you have, who art careful about the things of the Lord, to be holy both in body and spirit.
With those sayings there companies fear which has torment, which perfect charity casts forth; but with these sayings there companies chaste fear of the Lord, that abides for ever and ever. And to both kinds it must be said, “Be not high-minded, but fear;” that man neither of defense of his sins, nor of presumption of righteousness set himself up. For Paul also himself, who says, “For you have not received the spirit of bondage again to fear;” yet, fear being a companion of charity, says, “With fear and much trembling was I towards you:” and that saying, which I have mentioned, that the engrafted wild olive tree be not proud against the broken branches of the olive tree, himself made use of, saying, “Be not high-minded, but fear;” himself admonishing all the members of Christ in general, says, “With fear and trembling work out your own salvation; for it is God Who works in you both to will and to do, according to His good pleasure;” that it seem not to pertain unto the Old Testament what is written, “Serve the Lord in fear, and rejoice unto Him with trembling.”
Source: On Holy Virginity (New Advent)